By Raj Trikha
Changing Food Patterns has resulted in Diet-Induced Obesity
We live in a world with food readily available at our fingertips. From the moment we wake up to the time we settle into bed, we are constantly in a postprandial state. However, this was not always the case. Before the agricultural revolution 10,000 years ago, individuals were required to hunt and gather for their food, which reduced the availability of food. Our ancestral dietary patterns were much more restricted; undergoing extended periods of fasting before engaging in great feasts. Unfortunately, the current state of dietary affairs offer us the ease of having food readily available, which has contributed to the development of many chronic diseases.
Over the past few decades, research has examined how several of the most prevalent chronic diseases, namely cardiovascular disease (CVD), kidney disease, and non-alcoholic fatty liver disease (NAFLD), may be secondary diseases of diet-induced obesity. More recently, research has begun to analyze the beneficial effects of fasting for short durations; a phenomenon called intermittent fasting (IF). A common practice has included restricting one’s dietary intake to under 12 hours allowing for a greater time spent in the fasting period each day. This is called time restricted eating (TRE) and has been an interest of many of the current studies looking to attenuate diet-induced obesity and its associated diseases.
Time Restricted Eating Promotes Weight Loss
The underlying hypothesis behind TRE suggests that eating throughout the day and even into the night disrupts normal sleep-wake oscillations, called circadian rhythms. These circadian rhythms help regulate our metabolism by enhancing our ability to utilize carbohydrates, fat and protein through hormonal and enzymatic regulation. This idea was first demonstrated in a study published in the Journal of Diabetes in 1996, where individuals were fed a high sugar meal in the morning and the evening. The individuals were better able to handle the metabolic challenge during the morning compared with the evening. Using this idea as a foundation, a more recent study from 2012 evaluated metabolic outcomes in mice restricted to consume a high fat diet for 8 hours during their normal eating period. These animals were protected from weight gain compared to mice who consumed the same caloric intake, but over the course of 24 hours. This highlights that the benefits of TRE are independent of caloric restriction.
Collectively, these studies demonstrate that not eating according with one’s circadian rhythm may establish an alternative mechanism why mice gain additional weight on a high fat diet. Additionally, it suggests that the number of calories an animal consumes may not be the only factor regulating body weight. Future studies are needed to confirm if these results are consistent in when tested in a clinical population.
The Challenges of Incorporating TRE into Daily Life
There are many challenges faced when attempting to incorporate TRE into daily practice. Whether to skip breakfast and have your first meal at lunch, or to try to make it home early for dinner are two roadblocks inhibiting a smooth transition into TRE. Future studies will need to determine whether health benefits persist between both patterns, or if one is more favored over the other. However, for the time being, it might be safe to rely on grandma’s adage; breakfast is the most important meal of the day, and don’t eat anything after you leave the dinner table.
Peer-edited by Anandita Pal